Risks
The appropriate use of hyperbaric
oxygen is one of the safest therapeutic procedures available to the
modern practitioner. However, as with any medical therapy,
there are a few risks associated
with it. The most common are highlighted here:
v Barotrauma: Injury to the middle ear from an inability to properly equalize air pressure during
pressurization. External air pressure changes can cause discomfort
in the ear canal, whether it’s from flying in an airplane, driving over a mountain or undergoing a hyperbaric oxygen
treatment. This is caused by an imbalance of pressure in the middle ear. Most commonly, simply by swallowing, the pressure differences in the middle ear are
naturally rebalanced via the Eustachian tube and the ears equalize. Several techniques
are explained to the participants in order to facilitate the equalization process. Care
is taken by the technician to control or reduce the pressure until the ears equalize.
If applicable, in some cases, a decongestant may be recommended to reduce sinus fluids.
Some patients use EarPlanes®, sold over the counter in
many drug stores, which are small specialized ear plugs designed to reduce problems with equilibration. For persons
who are unable to equalize their ears after trying the above remedies, tiny pressure equalization tubes may be surgically
implanted in the ear before coming for therapy.
v Sinus Pain: Fluid build-up or a blockage in the sinus cavities may result in “sinus squeeze,” a temporary painful
condition which can be alleviated by slow compression or decongestants.
v Seizures. Oxygen-induced
seizures rarely occur during therapeutic HBO treatments. Increased neuro-activity
in the brain may result in a seizure for susceptible brain-injured patients as brain activity increases during therapy. On the contrary, many patients report a reduction in seizure activity in seizure-prone
patients over the course of treatments.
v Cataract formation: Studies
have shown that 7 of 15 patients receiving over 150 to 850 daily HBO treatments at pressures between 2.0 and 2.5
ATA developed new cataracts. Cumulative treatments spread over time had no effect
on cataract development.
v Pneumothorax: Patients
with a history of a collapsed lung may be more susceptible to having a spontaneous pneumothorax in chamber. This is an extremely rare occurrence.
v Dental Pain: An
air bubble trapped between the tooth and the filling may result in discomfort during treatment. Although rare, a small percentage of patients nationwide reported this discomfort.
v Oxygen Toxicity: Although
rare, it may occur in prolonged oxygen exposure under high pressure.
Common Side Effects
v Serous Otitis Media: An acute or chronic collection of fluid in the middle ear, where fluid cannot
drain down the Eustachian tube, either because of an upper respiratory infection or an attack of nasal allergy
or from long standing Eustachian tube blockage. This fluid may have thickened
so that it cannot be absorbed or drained easily. Hearing is diminished, similar to having “cotton in the ears.”
Normal hearing returns after a few weeks when the fluid is drained.
Sinus decongestants may help alleviate the blockage.
v Visual Refractory Changes: Over multiple treatments, pressure can also temporarily affect the lens of the eye and vision may worsen or
improve. Typically, patients with presbyopia may notice a vision improvement;
those with myopia may notice blurriness. Each of these refractory changes reverts
to pre-hyperbaric condition usually within 6 weeks after cessation of therapy.
v Alternobaric Vertigo: A sudden brief disorientation may
occur when the pressure is reduced at the end of a treatment.
v Confinement Anxiety: About
1 in 50 patients experiences anxiety during treatments. Calming techniques can
be employed to reduce the anxiety and if necessary and appropriate, a mild sedative may be taken before treatment.
v Numbness
in fingers: Tingling in the fourth and fifth fingers of the
hands has occurred in a small percentage of patients nationwide. This disappears
a few weeks after cessation of therapy.
